A North East MEP says Liverpool's plans to start and end cruise holidays will affect business at the Port of Tyne.
The city council was given a £20 million grant to build a new terminal at Pier Head, which port chiefs want to use for turnaround cruises.
The move would normally breach state aid rules. But the Department for Transport has said it would allow the rules to be lifted if the council repays some of the money.
Conservative MEP Martin Callanan says the plans are "unfair" to ports who have not received similar funding, and that Liverpool should be forced to pay back the UK and EU grants in full before proceeding.